Magnetically actuated sealed contact

ABSTRACT

A sealed contact for use in electromechanical relays has a flat base plate consisting of an annular outer member and a discshaped inner member joined together by means of a glass seal. A hood-shaped cover containing an armature holding spring and attached armature is sealed to the outer member of the base. The uniformly flat base and cover allow the contact to be used in a wide variety of electromechanical relays.

United States Patent 1191 Mecklenburg et al. A

[ MAGNETICALLY ACTUATED SEALED CONTACT [75] Inventors: Wolfgang Mecklenburg, Asperg;

Alfred Leicht, Stuttgart; Walter Hoffmann, Munklingen; Hans Dieter Pfeil, Mainz; lngo Rudiger Isert, Bietigheim; Helmut lButtel, Leonberg-Etlingen; Richard Braunschweig, Stuttgart; Philip John Smith, Kornwestheim, all of Germany [73] Assignee: International Standard Electric Corporation, New York, N.Y.

[22] Filed: Nov. 21, 1973 [21] Appl. No.: 417,984

[30] Foreign Application Priority Data Dec. 1, 1972 Germany 2258922 [521 US. Cl. 335/196, 335/151 [51] 1111. Cl. .1 ..110111 47/00 [58] Field of Search ..335/l96, 151,152,153,

1451 Feb. 25, 1975 [56] References Cited UNITED STATES PATENTS 3,020,369 2/1962 Jacobson 335/179 3,061,696 10/1962 Peek, Jr. 335/236 3,150,244 9/1964 Nitsch et al 335/196 3,458,839 7/1969 l-leetman 335/153 3,711,798 l/l973 Richert 335/153 Primary Examiner-Harold Broome Attorney, Agent, or Firm-John T. OHalloran; Menotti J. Lombardi, Jr.; Richard A. Menelly [57] ABSTRACT A sealed contact for use in electromechanical relays has a fiat base plate consisting of an annular outer member and a disc-shaped inner member joined together by means of a glass seal. A hood-shaped cover containing an armature, holdingspring and attached armature is sealed to the outer member of the base. The uniformly flat base and cover allow the contact to be used in a wide variety of electromechanical relays.

7 Claims, 18 Drawing Figures 1 MAGNETICALLY ACTUATED SEALED CONTACT BACKGROUND OF THE INVENTION The present invention relates generally to sealed contacts capable of being magnetically actuated. One such contact currently in use has a cover which includes an armature and an armature holding spring. The cover is sealed to a base plate having a pin connected thereto usually by means of a glass ring type seal. A pair of electrical contacts is provided, one on the armature, and one at the end of the pin internal to the contact. The pin mainly extends perpendicular from the base plate and serves as the magnetizing core for an electromagnet. A magnetizing coil wound around the pin exterior to the contact serves to provide energizing current to the electromagnet assembly. Current through the coil creates a magnetic field within the pin thereby exerting a magnetizing force upon the armature. The armature is pulled into contact with the base plate so that the electrical contact on the armature contacts the corresponding electrical contact on the base plate. When current ceases to flow through the magnetizing coil, the magnetic field collapses, and the armature is pulled back away from the base plate due to the restoring force created by the armature holding spring, thereby breaking the electrical connectin created between the pair of electrical contacts. This particular contact configuration where the elctromagnet is an integral part of the contact seriously limits the use of this contact in various applications. One problem inherent in this contact is due to the fact that the contact is limited to single contact operation in that only one contact can be operated by one electromagnet. Many applications require the use of more than one contact operation by a single electromagnet. This invention therefore overcomes the disadvantages of prior contacts by providing a contact which can be used in most applications, and which allows more than one contact to be actuated by a single electromagnet.

SUMMARY OF THE INVENTION An object of the invention is to provide an improved sealed contact capable of magnetic actuation.

According to the broader aspects of the invention this is accomplished by a base plate consisting of a ringshaped outer part and a disc-shaped inner part which are joined together by means of a glass ring, and an armature arranged opposite a section of the inner part as well as opposite a section of the outer part.

In this contact the glass-to-metal seal can be established in a very inexpensive way, for example by simply placing the outer part, the glass ring and the inner part on aplane plate of graphite. In so doing there is not required any additional positioning with the aid of holding parts. Subsequently to the sealing process, both the inner part and the outer part are in one plane at least on one side of the base plate.

According to one embodiment of the invention the inner part is made from a magnetically conductive material.

It is another object of the invention to provide a contact that can be used for the most types of relays when the material for both the outer part and the cover are selected accordingly.

According to a further embodiment of the invention, both the outer part and the cover are made from a nonmagnetic material.

In further embodying the invention, the outer part may be made from a non-magnetic material while the cover is made from a magnetically conductive material.

According to a further embodiment of the invention, both the outer part and the cover are made from a magnetically conductive material.

According to another embodiment of the invention the outer part is made from a magnetically conductive material while the cover is made from a non-magnetic material.

When using these combinations of material it is possible to obtain monostable as well as various bistable relays, the armatures of which, in the closed condition of the contacts, and for obtaining an optimum design of the magnetic circuit of the respective relay type, being either arranged slopingly in relation to the base plate, or placed in parallel on the base plate.

BRIEF DESCRIPTION OF THE DRAWINGS Further embodiments of the invention, especially the features of the aforementioned various arrangements of the described contact in electromagnetic relays, will be described herein in greater detail and more easily understood if reference is made to the following drawings in which:

FIG. 1 shows a top view ofa sealed contact with a flat housing;

FIG. 2 shows a side cross sectional view of the contact shown in FIG. 1;

FIG. 3 shows a bottom view of the contact shown in FIG. 1;

FIG. 4 shows a cross sectional side view of one embodiment of a spring armature arrangement when the contact is actuated;

FIG. 5 shows a cross sectional side view of another spring armature arrangement when the contact is actuated;

FIG. 6 shows a cross sectional side view of a further embodiment of an armature spring arrangement when the contact is actuated;

FIG. 7 shows a cross sectional view of another embodiment of a spring contact arrangement when the contact is actuated;

FIG. 8 shows a cross sectional side view of an electromagnetic relay with several sealed contacts in a stacked arrangement;

FIG. 9 shows a cross sectional side view of an electromagnetic relay with two sealed contacts arranged next to each other;

FIG. 10 shows a cross sectional side view of an electromagnetic relay with two contacts facing one another;

FIG. 11 shows a top cross sectional view of the relay of FIG. 10;

FIG. 12 shows a side view of the relay shown in FIGS. 10 and II;

FIG. 13 shows a side view of the relay shown in FIG. 12 partially in cross section;

FIGS. l4, l5 and 16 show different magnetically conducting stamped sheet-metal parts for use in the relays according to FIGS. 12 and 13, in a three-dimensional representation;

FIG. 17 shows a cross sectional side view of an electromagnetic locking relay with two contacts facing one another; and

FIG. 18 shows a cross sectional side view of the locking relay shown in FIG. 17.

DESCRIPTION OF THE PREFERRED EMBODIMENT According to FIGS. 1-3 there is illustrated a sealed contact, the housing of which consists of a plane base plate and a hood-shaped cover 1. The rim portion of the cover 1 is firmly joined to the base plate either in a dust-proof manner or hermetically sealed. Sealing can be established, for example, by means of an annular sealing weld (welded joint). The base plate of the contact consists of a ring-shaped outer part 2 and a disc-shaped inner part 3 which, with the aid of a glass ring 4. and by employing the known glass-to-metal sealing method, are in such a way joined together as to be lying in one plane at least on the inside of the base plate. The inner part 3 is arranged eccentrically within the outer part 2. An armature designed as a flat component, is fastened to the inside of the cover 1 by means of an armature holding spring 6, and is thus arranged opposite a section of the inner part 3 as well as opposite a section of the outer part 2. In order to be able to compensate for manufacturing or wear tolerances, the surface of the armature S cooperating with the inner part 3, may have a bulged or spherical design.

The flat, disc-shaped contact described with reference to FIGS. l-3 can be used in a diversified manner in neutral, various bistable, or rest contact relays. These relays all require a different mode of operation of the armature 5 which, depending on the design of the magnetic circuit of the relay, must be arranged either slopingly or parallel in relation to the base plate when in the actuated state. The different mode'of operation of the contact can also be achieved by suitably se-' lecting the'material for the outer part 2 and the cover 1. A sloping armature position will be achieved, for example, in cases where the outer part 2 is made from a non-magnetic material; in this case the cover 1 may be either magnetic or non-magnetic (FIGS. 4 and 5). A parallel armature position will result whenever the outer part2 is made from amagnetic material; in this case the cover 1 may either be magnetic or nonmagnetic (FIGS. 6 and7). In all of these cases, however, the inner part3 is made from a magnetically conductive material.

Four corresponding examples of embodiment are shown in FIGS. 4-7. FIGS. 4 and 5 each show a contact employing a non-magnetic outer part 2, with the armature 5, in its actuated condition, being in a sloping position in relation to the base plate. In FIG. 4 the fastening point 7 for the armature holding spring 6 at the cover 1 is positioned over the outer part 2. In FIG. 5 the cover 1 is shown to be turned by 180, so that the fastening point 7 of the armature holding spring 6 at the cover 1 is positioned over the inner part 3. FIGS. 6 and 7 each show a contact with a magnetic outer part 2, so that the armature 5., in' its actuated state, is positioned in parallel with the base plate. In this way it is possible to achieve an increased adhesion with respect to a closed contact. Likewise in FIGS. 6 and 7, there are shown various arrangements of the fastening points 7 of the armatureholding spring 6 at the cover 1, above the outer part 2 (FIG. 6),.and above the inner part3 (FIG. 7);

FIG. 8 shows a neutral electromagnetic relay with three stacked sealedcontacts 8, 9 and 10, which are all capable of being actuated by means of an electromagone pole of the electromagnet 11 is coupled to th inner part 3 of the lowest'contact 8 in the stack via a flux guide member 12 while the other pole thereof, via a flux guide member 13, is magnetically connected to the cover 1 of the top contact 10 in the stack. The outer parts 2 of the contacts 8, 9, 10 are made from a nonmagnetic material while the covers 1 are preferably made from a magnetically conductive material. The covers 1, however,.may justas well be made from' a non-magnetic material. The inner parts 3 are each provided with a soldering terminal 15, with the aid of which there are established the electrical connections to the individual contacts 8, 9, l0.

FIG. 9 shows a further neutral electromagnetic relay with two juxtaposed contacts l6, l7 capable of being actuated by an electromagnet l8 lying therebetween. The one pole of the electromagnet 18 is coupled via flux guide members 19 to the inner parts 3 of the contacts 16 and 17 whereas the other pole thereof, via flux guide members 20, is magnetically connected to the covers 1 ,of the contacts 16 and 17. The outer parts 2 of the contacts 16, 17 are made from a non-magnetic material. The covers 1 may be either of a magnetically conductive or non-magnetic material. The inner parts 3 are each provided with soldering terminals 14, and the covers 1 are each provided with soldering terminals 15 for leading out the electrical connections radially in relation to the contacts 16 and 17.

Other types of embodiments of neutral electromagnetic relays will be obtained when combining stacked and juxtaposed contacts with one another for being actuated by one common electromagnet.

FIGS. 10 and 11 show an electromagnetic relay comprising two sealed contacts 21, 22 with the base plates thereof facing one another. Between the two base plates of the contacts 21, 22 there is arranged one permanent magnet 23 and one electromagnet24 which are magnetically in series via the contacts 21, 22. The electromagnet consists of a magnetically conductive pin 24 and of a magnetizing winding 25 and is'applied to the oppositely arranged inner parts 3 of the contacts 21, 22. The permanent magnet 23 is respectively coupled with one of its poles, next to the electromagnet, to the oppositely arranged surfaces of the outer parts 2 The distance between the oppositely arrangedbase. plates is chosen thus that in the gap or interspace 26 between the two base plates there will be obtained a shunt characteristic for the permanent magnet 23 and a series characteristic for the electromagnet 24, 25. In the sectional view shown in FIG. 11, the shunt area is indicated by the reference numeral 27.

The same relay construction as shown in FIG. 10 can be used to obtain various types of relays. The permanent magnet 23 produces in the magnet circuit of the relay a pre-excitation, the amount of which being dependent upon the dimensions of the magnet and the magnetizing force, as well as uponthe magnetic circuit of the relay. In cases where the pre-excitation is smaller than the drop-out or release excitation, there will be obtained a neutral relay with reduced pick-up and drop-out values. In cases where the pre-excitation is greater thanthe hold value, the relay is of the bistable type. If finally the pre-excitation by the permanent magnet 23 exceeds the pick-up excitation of the neutral relay, there will be obtained a relay with rest contacts. These three types of relays can be realized by correspondingly decreasing the magnetism of a sufficiently tion to the plane of thebase plates closely next to each other and aresurrounded by a common magnetizing coil or winding 32. The stampedmetal parts 30, 31 are each provided with an extension serving as a soldering lug 33 or 34, for leading out one of the electrical terminals radially in relation to the contacts 28 or 29 respectively. The other electrical connection of the contacts 28, 29, as described hereinbefore, is established by means of a soldering terminal as attached to the cover 1.

FIGS. 14, 15 and 16 show different types of magnetically conductive stamped metal parts 35, 36 and 37 with soldering lugs or terminals 38,39 and 40, suitable for being used in the relays shown in FIGS. 12 and 13. The angled-off ends at which the stamped metal-parts 35, 36, 37 are welded to the inner parts 3, are indicated by the reference numerals 41, 42 and 43 respectively. In-the relays with the oppositely arranged base plates as shown in FIGS. 10 to 13, the outer parts 2 are made from a magnetically conductive material, and the covers 1 are madeifrom a non-magnetic material. The covers 1, however, can be made equally well from a magnetic material.

The mode of operation of the relays shown in FIGS. 10 to 13 will not be described with respect to the case where the permanent magnet 23 is dimensioned for the use in a magnetic locking relay. When the contacts e.g., 21, 22 are open, the majority of the permanent magnetic flux 23, via the shunt (gap or interspace 26) will flow between the two base plates through air. If, in response to a short-duration excitation of the magnetizing winding 25 (FIG. 10) or 32 (FIGS. 12 and 13') a magnetic flux is produced in series with the permanent.

magnet 23, then a considerable flux 'will flow via the armatures 5 and attract the latter to the base plates. Owing to. the series arrangement of the contacts e.g., 21, 22 (FIG. 10) in relation to the magnetic flux, there will always be closed both of the contacts 21, 22. The armatures S are applied flatly-to the base plates. The armatures 5 are released in response to a shortduration excitation of the magnetizing winding e.g., 25 (FIG. 10) in the opposite direction.

FIG. 17 shows an electromagnetic locking relay with two sealed contacts 44 and 45 of which the covers 1 are arranged to face one another. Between the two covers 1 of the contacts 44 and 45 there is arranged a permanent magnet23 and an electromagnet. The electromagnet consists of a magnetically conductive pin 24 and of a magnetizing coil (winding) 25. The pin 24 is applied almost coaxially with the inner parts 3 to the oppositely arranged covers 1. Located next to the electromagnet,

the permanent magnet 23 is magnetically coupled by means of its poles to the covers 1. The inner parts 3 of the two contacts 44 and 45 are magnetically connected to one another by means of a flux guide member 46 surrounding the two contacts 44, 45 in a U-shaped manner. Of the contacts 44, 45 the outer parts 2 as well as the covers 1 are made from a non-magnetic material.

The magnetic flux of the closed contacts 44, 45 extends from the inner part 3 to the armature 5 and leaves the contact 44 or 45 at the end of the armature holding spring 6 through the non-magnetic cover 1. The percussive strength is achieved in this case not by the initial tension but by the magnetic bias, this will become clearly evident from the following explanation of the magnetic flux path in the open contact. In the opened condition of the contacts 44, 45 the majority of the flux of the permanent magnet 23 extends via the shunt, i.e., via the armature 5 and the magnetically conductive pin 24. If, in response to a short-duration excitation of the magnetizing winding 25, a magnetic flux is produced in the pin 24, with this flux being directed oppositely to the flux of the permanent magnet, then the flux of the permanent magnet 23 will be displaced and caused to flow via the air gaps toward the inner parts 3-and back via the flux guide member 46. On account of this the armatures 5 are attracted with their free ends by the inner parts 3, thus assuming a sloping position. In the case of an opposite excitation 'of the magnetizing winding 25, the armatures 5 are attracted by the covers 1. It is an advantage with respect to this magnetic principle when the covers 1 are made from a very thin nonmagnetic material.

FIG. 18 shows a further type of magnetic locking relay comprising two sealed contacts 47 and 48 with the covers 1 thereof facing one another. Between the two covers 1 there is arranged a permanent magnet 23 as well as a magnetically conductive pin 24. This pin 24 is applied almost coaxially with the innerparts 3.to the covers 1 facing one another. Next to thepin 24, the permanent magnet 23 is magnetically coupled by means of its poles to the cover 1. The inner parts 3 are magnetically connected to one another by means of a flux guide member 49 consists of two parallel extending legs 50, 51 on which there is each time arranged one coil 52 or 53 for being controlled by various coordinates X or Y of a cross point matrix respectively. The outer parts 2 and the covers 1 of the two contacts 47 and 48 are made from a non-magnetic material. 7

The magnetic locking relay according to FIG. 18 is actuated as follows: In the open state of the contacts 47, 48 the majority of the flux of the permanent magnet 23 extends via the armatures 5 and the magnetically conductive pin 24 between the two covers 1. If both of the coils 52 and 53 are subjected to a short-duration excitation in the same sense and produce a magnetic flux in series with the permanent magnet 23, then the flux via the armatures 5 towards the inner parts 3 is intensifiedthus causing the contacts 47 and 48 to close. If only one of the coils e.g., 52 is excited then the magnetic flux as produced thereby is shorted via the other leg 51. The contacts 47 and 48 are only actuated upon simultaneous excitation of both the coils 52 and 53. Accordingly, the relay will only operate when being controlled simultaneously via the two coordinates X and Y-of eg, a cross point matrix. The flux of the permanent magnet 23 causes the armatures 5 to be retained in both positions.

In the relays shown in FIGS. 8 to 13, I7 and 18 the two oppositely arranged contacts are insulated from one another by means ofa foil or a suitable plastic coating.

While we have described above the principles of our invention in connection with specific apparatus, it is to be clearly understood that this description is made only by way of example and not as a limitation to the scope of our invention as set forth in the objects thereof and inthe accompanying claims.

What is claimed is:

1. An electromagnetic relay including contacts of the type with a base plate having outer and inner parts joined together by means of a glass ring, a hood-shaped cover sealedto the outer part of the base plate, an armature holding spring mounted to the inner surface of the cover, and an armature attached to the spring in a position opposite the inner member for making contact therewith, comprising:

a. a plurality ofcontacts arranged in a stack such that the base plate of each contact in the stack is opposite the cover of the next lowest contact; and

b. an electromagnet magnetically coupled to said stack by means of a pair of first and second flux guide members, wherein said first flux guide mem her is magnetically coupled to the cover of the topmost contact in the stack, and said second flux guide member is magnetically coupled to the inner part of the lowest contact in the stack.

2. An electromagnetic relay including contacts of the type including a base plate having outer and inner parts joined together by means of a glass ring, a hood-shaped cover sealed to the outer part of the base plate, an armature holding spring mounted to the inner surface of the cover, and an armature attached to the spring in a position opposite the inner member for making contact therewith, comprising:

a. a plurality of contacts arranged in a pair offirst and second stacks, each stack having an inner part of the upper contact opposite a cover of the next lowest contact in the stack; and b. an electromagnet having a pair of first and second flux guide members such that said first and second stacks are arranged one on either side of said electromagnet so that said first flux guide member is magnetically coupled to the covers of the topmost contacts in said first and second stacks, and said second flux guide member is magnetically coupled 8 to the inner parts of the bottom-most contacts in said first and second stacks whereby said plurality of contacts are capable of being actuated by said electromagnet. 3. A sealed contact capable of magnetic actuation comprising:

a base plate having a flat disc-shaped nonmagnetically conductive outer part and a flat discshaped magnetically conductive inner part, said inner and outer parts being arranged eccentrically within the same geometric plane and sealed to each other by means of a glass ring;

a hood-shaped non-magnetically. conductive cover having a flange-like projection for scaling to said outer part by means of an annular weld;

an armature-holding spring attached to the inner surface of said cover at a point opposite said outer part; and

an armature attached to said spring opposite said inner part, said armature having a spherical configuration on one surface thereof for providing electrical contact with said inner part, whereby a plurality of said contacts are capable of being ar ranged in a stack such that the base plate of each contact in the stack is opposite the cover of the next lowest contact therewithin said stack.

4. The sealed contact of claim 3 wherein said outer part is made from a non-magnetically conductive material and wherein said cover is made from a magnetically conductive material.

5. The sealed contact of claim 3 wherein the fastening point of said armature-holding spring to the cover is located opposite said inner part.

6. The sealed contact according to claim 3 wherein said outer part and said cover are made from magnetically conductive material.

7. The sealed contact according to claim 3 wherein said outer part is made from a magnetically conductive material and said cover is made from a nonmagnetically conductive material. 

1. An electromagnetic relay including contacts of the type with a base plate having outer and inner parts joined together by means of a glass ring, a hood-shaped cover sealed to the outer part of the base plate, an armature holding spring mounted to the inner surface of the cover, and an armature attached to the spring in a position opposite the inner member for making contact therewith, comprising: a. a plurality of contacts arranged in a stack such that the base plate of each contact in the stack is opposite the cover of the next lowest contact; and b. an electromagnet magnetically coupled to said stack by means of a pair of first and second flux guide members, wherein said first flux guide member is magnetically coupled to the cover of the topmost contact in the stack, and said second flux guide member is magnetically coupled to the inner part of the lowest contact in the stack.
 2. An electromagnetic relay including contacts of the type including a base plate having outer and inner parts joined together by means of a glass ring, a hood-shaped cover sealed to the outer part of the base plate, an armature holding spring mounted to the inner surface of the cover, and an armature attached to the spring in a position opposite the inner member for making contact therewith, comprising: a. a plurality of contacts arranged in a pair of first and second stacks, each stack having an inner part of the upper contact opposite a cover of the next lowest contact in the stack; and b. an electromagnet having a pair of first and second flux guide members such that said first and second stacks are arranged one on either side of said electromagnet so that said first flux guide member is magnetically coupled to the covers of the topmost contacts in said first and second stacks, and said second flux guide member is magnetically coupled to the inner parts of the bottom-most contacts in said first and second stacks whereby said plurality of contacts are capable of being actuated by said electromagnet.
 3. A sealed contact capable of magnetic actuation comprising: a base plate having a flat disc-shaped non-magnetically conductive outer part and a flAt disc-shaped magnetically conductive inner part, said inner and outer parts being arranged eccentrically within the same geometric plane and sealed to each other by means of a glass ring; a hood-shaped non-magnetically conductive cover having a flangelike projection for sealing to said outer part by means of an annular weld; an armature-holding spring attached to the inner surface of said cover at a point opposite said outer part; and an armature attached to said spring opposite said inner part, said armature having a spherical configuration on one surface thereof for providing electrical contact with said inner part, whereby a plurality of said contacts are capable of being arranged in a stack such that the base plate of each contact in the stack is opposite the cover of the next lowest contact therewithin said stack.
 4. The sealed contact of claim 3 wherein said outer part is made from a non-magnetically conductive material and wherein said cover is made from a magnetically conductive material.
 5. The sealed contact of claim 3 wherein the fastening point of said armature-holding spring to the cover is located opposite said inner part.
 6. The sealed contact according to claim 3 wherein said outer part and said cover are made from magnetically conductive material.
 7. The sealed contact according to claim 3 wherein said outer part is made from a magnetically conductive material and said cover is made from a non-magnetically conductive material. 